This interpretation is only one of many. My approach has been to look at these data and systematically examine how alternative explanations could explain these trends. The idea that the incidence is increasing should only be accepted if alternative explanations can confidently be ruled out. Differences in ascertainment (the ability to identify cases in surveys) and diagnostic concepts and criteria are still significant issues.
Some states use only medical records, others use both medical and educational records. If next time all states include educational sources, the rates will go up, not because of an increased incidence but because the method will be more efficient at identifying cases.
I noted some methodological peculiarities in the survey methods employed in the two states with the highest rates.
Association for Science in Autism Treatment: In response to a newspaper article (http://asatonline.org/media_watches/79)
"Further, there have been a number of studies looking at the impact of changing diagnostic criteria and diagnostic substitution on the prevalence rates of autism. Those studies have shown that there is a relationship between diagnostic practice and prevalence rates; a large portion of the increase remains unexplained. In studies investigating this relationship, less than a third of the observed increase in prevalence of autism can be attributed to changes in diagnostic practice(Coo, et al., 2008; King & Bearman, 2009)."
Dr. Allen Frances:
The most direct opinion I have seen. On the reasons for the increase in autism diagnoses to 1 in 88 children:
Having the label can make the difference between being closely attended to in a class of four versus being lost in a class of 40. Kids who need special attention can often get it only if they are labeled autistic.
So the autism tent has been stretched to accommodate a wide variety of difficult learning, behavioral and social problems that certainly deserve help — but aren’t really autism. Probably as many as half of the kids labeled autistic wouldn’t really meet the DSM IV criteria if these were applied carefully.
Freeing autism from its too tight coupling with service provision would bring down its rates and end the “epidemic.” But that doesn’t mean that school services should also be reduced. The mislabeled problems are serious in their own right, and call out for help.
So where do we stand, and what should we do? I am for a more careful and restricted diagnosis of autism that isn’t driven by service requirements. I am also for kids getting the school services they need.
The only way to achieve both goals is to reduce the inordinate power of the diagnosis of autism in determining who gets what educational service. Psychiatric diagnosis is devised for use in clinical settings, not educational ones. It may help contribute to educational decisions but should not determine them.
Increasingly panicked, parents have become understandably vulnerable to quackery and conspiracy theories. The worst result has been a reluctance to vaccinate kids because of the thoroughly disproved and discredited suggestion that the shots can somehow cause autism.
Dr. Allen Frances, now a professor emeritus at Duke University’s department of psychology, chaired the DSM IV task force.